Amazon.com: BOSS Audio Systems R1100M Riot Series Car Audio Subwoofer Amplifier - 1100 High Output, Monoblock, Class A/B, 2/4 Ohm Stable, Low/High Level Inputs, Low Pass Crossover, Mosfet Power Supply, Stereo :
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Amazon.com: AUDIOTEK AT3500S 2 Channel Stereo Car Amplifier - 3500 Watts, 2 Ohm Stable, LED Indicator, Full Range, Bass Knob Included, Great for Speakers and Subwoofers : Electronics
2 Ohm Vs 4 Ohm Subwoofers - Which Is Better?
Deaf Bonce Car Audio 12" 2+2 Ohm Subwoofer MF-12R-D2 & Monoblock Amp P — Big Jeff Online Inc
Alpine W12S4 12" 250 Watt 4 OHM Subwoofers with GTR-601 Mono Subwoofer Amplifier 600 watts RMS x 1 at 2 ohms - Creative Audio